It would be great if the revenue could publish a list of those companies that it considered had acted fairly. I for one would be much happier spending my money with a company that the revenue could certify had acted properly.Nick Spencer, via email

The arduousness of the task that you have had to undertake to establish this basic information has no place in an open society. The first step toward a solution is simple: require all UK PLCs to publish the total amount of UK tax paid in their annual accounts. In some countries, all individual tax records are public, and there is a case for this too, though to be balanced against invasion of privacy. But corporations, while legal persons, have no privacy of that kind to be respected.Dr Melissa Lane, Kings College, Cambridge

You make me wonder whether the Guardian operates a pension scheme for its staff. Such arrangements would probably not exist were it not for the tax avoidance that they offer. But if you wanted to end tax avoidance by companies, why not consider abolishing corporation tax and raising the tax rate on dividends and interest paid by firms. Surely this is much simpler than tilting at windmills.Dr Martin Weale, London